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11/15/11 Indiana Department of Transportation HIGHWAY CERTIFIED TECHNICIAN PROGRAM TRAINING MANUAL Concrete Paving 11/15/11 Table of Contents Chapter One – Portland Cement Concrete Pavement Description….……………………………………………………………… 1-1 Types of Concrete Pavement ……………………………………………… 1-2 Plain Jointed Concrete Pavement Reinforced Jointed Concrete Pavement Continuously Reinforced Concrete Pavement Reinforced Concrete Bridge Approach Pavement Chapter Two – Preparation of the Grade Grade Preparation ……………………………………… 2-1 Subgrade ………………………………………………………………… 2-1 Subbase…………………………………………………………………… 2-2 Chapter Three – Concrete Job Control Materials …………….…………………………………………………… 3-1 Aggregates Portland Cement Fly Ash/GGBFS Water CMD Process…………………………………………………………… 3-6 Testing Equipment Calibration…………………………………………… 3-8 Reference Documents……………………………………………………. 3-8 Safety…………………………………………………………………… 3-5 Sampling Concrete………………………………………………………. 3-9 Sampling from Concrete Trucks Sampling from Grade Sampling from Central Mixed Plant Testing Concrete………………………………………………………… 3-13 Pressure Method for Air content Volumetric Method for Air Content Unit Weight and Relative Yield Slump Making and Curing Test Specimens in the Field Flexural Strength Water/Cementitious Ratio Curing Concrete ………………………… 3-16 Failed Materials………………………………………………………… 3-16 Chapter Four- Equipment Concrete Plants ……………………………………………………………. 4-1 Central Mix Plant Ready-Mix Plant Delivery Equipment ………………………………………………………. 4-3 Paving Equipment ………………………………………………………… 4-5 Finishing Machine Spreader Slip-Form Pavers Hand Placement Finishing Equipment Tining Machine Vibrators Hand Equipment ………………………………………………………… 4-9 10 Foot Straightedge Tining Hand-Held Vibrators Saws …………………………………………………… 4-11 Forms …………………………………………………………………… 4-12 Chapter 5 – Setting Forms Form Fitness ……………………………………………………………… 5-1 Subbase Support ……………………………………………………… 5-2 Form Setting ……………………………………………………………… 5-2 Grade and Alignments ………………………………………………… 5-2 Chapter 6 – The Paving Operation Condition of Subbase…………………………… 6-1 Dowel Bars and Assemblies ……………………………………………… 6-2 Mixing Concrete ……………………………………… 6-4 Weather Restrictions …………………………………………………… 6-6 Placing Concrete ……………………………………………………… 6-6 Placing Reinforcing Steel …………………………………………… 6-8 Strike Off, Consolidation, and Finishing ………………………………… 6-9 Floating Checking Finish and Surface Corrections Tining Edging Edge Slump …………………………………………………………… 6-15 Permanent Dates and Stations …………………………… …………… 6-15 Curing …………………………………………………………………… 6-17 Wet Burlap Wet Straw Waterproof Blankets Liquid Membrane Forming Compound Protection from Rain ……………………………………………………… 6-18 Removal of Forms ………………………………………………………… 6-19 Chapter 7 – Pavement Joints Types of Joints …………………………………………………………… 7-2 Construction Joints D-1 Contraction Joints Longitudinal Joints Transverse Construction Joints Terminal Joints Expansion Joints Retro-fitted Tie Bars Chapter 8 – Other Pavement Details and Requirements Ear Construction …………………………………………………… 8-1 Pavement Smoothness …………………………………………………… 8-1 Protection of Pavement …………………………………………………… 8-3 Opening Pavement to Traffic ……………………………………………… 8-3 Construction Vehicles Non-Construction Vehicles Pavement Thickness …………………………………………… 8-4 Coring Core Measurements Deficient Pavement Thickness…………………………………………… 8-5 Method of Measurement and Basis of Payment ………………………… 8-6 Chapter Nine- Concrete Pavement Patching Materials ………………………………………………………………… 9-1 Concrete Mix Design……………………………………………………… 9-2 Concrete Mix Criteria……………………………………………………… 9-2 Trial Batch Demonstration of CMDS……………………………………… 9-3 Acceptance………………………………………………………………… 9-3 Removal of Concrete……………………………………………………… 9-3 Partial Depth Patches Full Depth Patches Placement of Patching Materials………………………………………… 9-5 Partial Depth Patches Full Depth Patches Curing/Opening to Traffic………………………………………………… 9-8 Method of Measurement…………………………………………………… 9-8 Basis of Payment……………………………………………………………9-8 Chapter 10 – QC/QA PCCP and PCCP Sublots and Lots…………………………………………………………… 10-1 Random Sampling………………………………………………………… 10-2 Random Numbers Sample Location – Plastic Concrete Sample Location – Cores Sampling Procedure Trial Batch Demonstration………………………………………………… 10-8 QA Testing………………………………………………………………… 10-9 Flexural Strength Air Content Unit Weight Water/Cementitious Thickness Smoothness Pay Factors…………………………………………………………………. 10-11 Flexural Strength Air Content Thickness Smoothness Quality Assurance Adjustment…………………………………………… 10-12 Flexural Strength, Air Content, Air Content Range Thickness Smoothness Total Quality Assurance Adjustment Failed Materials…………………………………………………………… 10-15 Appeals…………………………………………………………………… 10-15 Flexural Strength Appeal for Sublot Air Content Appeal for Sublot PCCP Acceptance…………………………………………………………. 10-15 1 Portland Cement Concrete Pavement Description Types of Concrete Pavement Plain Concrete Pavement Plain Jointed Concrete Pavement Reinforced Jointed Concrete Pavement Continuously Reinforced Concrete Pavement Reinforced Concrete Bridge Approach Pavement 1-1 CHAPTER ONE: PORTLAND CEMENT CONCRETE PAVEMENT The pavement is the portion of the road that vehicles come in direct contact with. A rough pot-holed pavement is hard on vehicles and uncomfortable to the motorist. For these and many other reasons, a structurally sound, smooth riding, and long lasting pavement is very important. A quality pavement requires materials and construction practices in accordance with the design and specifications for the pavement. Those responsible for this quality are required to know how the pavement is built, the design and specifications requirements, and how to check for compliance of the design and specifications. There are several types of concrete pavements and requirements for their corresponding contraction joints. This chapter discusses the different types of concrete pavements and where to find the requirements for the pavements in the contract documents. ______________________________________________________________ DESCRIPTION PCCP is composed of Portland cement concrete and, when specified, reinforcing steel and various joint materials. Concrete pavement is placed at the thickness specified in the plans or proposal and is constructed on a subbase course as required by the contract documents. The pavement is placed in reasonably close conformance to the lines, grades, and typical cross-sections (Figure 1-1) shown in the plans. Concrete basically consists of Portland cement, water, and fine and coarse aggregates. A pozzolan material, such as fly ash, may be added to the concrete mix as a partial substitute for cement. The curing of the concrete is a chemical reaction of the Portland cement and water, which causes the concrete to shrink and crack. To control the cracking, transverse joints and longitudinal joints are constructed in the pavement. All pavements require transverse joints to control transverse cracking. These are sometimes known as contraction joints. Pavements wider than 16 feet require longitudinal joints to control longitudinal cracking. Pavements with transverse joints are referred to as jointed pavements. TYPES OF CONCRETE PAVEMENT PLAIN JOINTED CONCRETE PAVEMENT Plain jointed concrete pavement has no longitudinal reinforcing steel but is constructed with transverse joints (joints from edge of pavement to edge of pavement). The types of joints used are shown in Figure 1-1. Nearly all concrete pavements constructed by INDOT are of this type. Figure 1-1. Plain Jointed Concrete Pavement REINFORCED JOINTED CONCRETE PAVEMENT Reinforced jointed concrete pavement is reinforced with steel mesh and is built with transverse joint spacing of 40 ft. Historically, this type of pavement was the predominant concrete pavement built by INDOT. CONTINUOUSLY REINFORCED CONCRETE PAVEMENT Continuously reinforced concrete (CRC) pavement is reinforced with a large amount of longitudinal steel (No. 5 bars, 6 inches on center) and only longitudinal joints as required. There are no transverse joints in this type of pavement. INDOT no longer builds CRC pavements. However, many of these pavements still exist and patching existing CRC pavements present some challenges compared to other types of concrete pavements. REINFORCED CONCRETE BRIDGE APPROACH PAVEMENT Reinforced concrete bridge approaches are built at the ends of a bridge with a minimum length of 20 ft. They are generally reinforced with two mats of steel and are built to a specified thickness. The purpose of a bridge approach is to eliminate settlement of the pavement at the bridge ends. Since the bridge end bents are usually on piles, the bridge does not settle, but the end bent backfill usually experiences some settlement. The reinforced concrete bridge approach pavement is usually supported by a pavement ledge on the bridge end and a terminal joint on the end adjacent to the concrete pavement. Additional information regarding reinforced concrete bridge approaches can be found in the 609-RCBA series of INDOT Standard Drawings. 2 Preparation of the Grade Grade Preparation Subgrade Subbase [...]... subgrade is required to be well drained at all times No subbase may be placed if the subgrade is frozen or muddy The subgrade is required to be finished to within 1/2 in of the true grade This is important as there is a deduction for thin pavement This deduction may be made for deficiencies greater than one tenth of an inch In form paving, these tolerances are usually accomplished with a machine called... of subbase The technician needs to keep a permanent record of all depth checks, including the date, location, and thickness of all checks This record needs to be submitted with the final construction record to verify the quantity of material actually placed If deficiencies are found in the thickness, appropriate measures are required to be taken If more material is required, the additional material is... central-mix plant this process occurs in the mixing drum, and in a transit mix this process occurs in the truck mixer Only clean, potable water shall be used Contaminated water may contain materials which are detrimental to the concrete after placement After the water is added to the mix for concrete associated with PCC base, QC/QA PCCP, or PCCP, the concrete is required to be placed within 90 minutes... yard of paving concrete contains 564 lbs or six bags of cement In order to verify that the concrete used in pavement meets this requirement, the Technician will perform a unit weight/relative yield test at the paving site as soon as the first load begins discharging The results of this test determine the actual amount of cement in each cubic yard of concrete If the cement content is determined to be... Portland-pozzolan cement, Type IP-A is similar to Type I-A, except that this cement also contains a pozzolan When Portland cement, Type IP-A is used, fly ash/GGBFS specifications regarding allowable calendar periods apply Portland cement, Type III obtains a high early strength Portland cement, Type III-A is similar to Type III except that this cement contains entrained air from the manufacturing process... trucks equipped with agitators If the hauling vehicles have no agitators, this time is reduced to 30 minutes if the concrete temperature is 90◦F or above and 45 minutes for cooler temperatures The time the water is added to the concrete is stamped on the ticket at the concrete plant For patching mixtures, the concrete must be placed within 30 minutes of the time that water is added if hauled in a truck... within 30 minutes of the time that water is added if hauled in a truck with no agitators If the truck has agitators or if a truck mixer is used, the concrete must be placed within 90 minutes of the time that water was added or within 30 minutes of introduction of calcium chloride solution, whichever is less The amount of water added at the plant varies from day to day depending upon the moisture contents... shortly after production begins If random sampling requires that an acceptance test is to be performed during this first day of production, the acceptance testing can be used by the Technician to evaluate the new concrete mix design If any Technician’s test result from samples taken during this first day of production indicates a failure to meet the specification requirements, the Technician must notify... IN THE FIELD AASHTO T 23 is the test method used for making and curing concrete test specimens in the field This procedure includes the methods used for flexural strength beams 3-13 FLEXURAL STRENGTH AASHTO T 97 is the test method used for determining the flexural strength of concrete beams This test consists of breaking the test beams on a selfrecording beam breaker and calculating the flexural strength... responsible for performance of the concrete mix design process, CMD The Specifications outline the requirements of the process and additional information regarding the CMD process is included later in this chapter AGGREGATES As mentioned previously, concrete mixes include two aggregate types Fine aggregates are sands, usually meeting No 23 aggregate gradation requirements Concrete used in QC/QA PCCP